INFO: task bch-copygc/loop:5250 blocked for more than 143 seconds. Not tainted 6.11.0-syzkaller-02520-gadfc3ded5c33 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:bch-copygc/loop state:D stack:20272 pid:5250 tgid:5250 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x17ae/0x4a10 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6621 __closure_sync+0x259/0x2f0 lib/closure.c:146 bch2_wait_on_allocator fs/bcachefs/alloc_foreground.h:238 [inline] __bch2_write+0x55a7/0x5d20 fs/bcachefs/io_write.c:1506 bch2_write+0x947/0x1670 fs/bcachefs/io_write.c:1633 closure_queue include/linux/closure.h:270 [inline] closure_call include/linux/closure.h:432 [inline] bch2_data_update_read_done+0x22e/0x330 fs/bcachefs/data_update.c:423 move_write fs/bcachefs/move.c:133 [inline] bch2_moving_ctxt_do_pending_writes+0x44c/0x8d0 fs/bcachefs/move.c:164 move_buckets_wait+0x2ba/0x1290 fs/bcachefs/movinggc.c:114 bch2_copygc_thread+0x83f/0xc20 fs/bcachefs/movinggc.c:386 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e738660 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline] #0: ffffffff8e738660 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e738660 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6626 2 locks held by getty/4975: #0: ffff88803096b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002efe2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 2 locks held by syz-executor114/6056: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-syzkaller-02520-gadfc3ded5c33 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xff4/0x1040 kernel/hung_task.c:379 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 5234 Comm: sshd Not tainted 6.11.0-syzkaller-02520-gadfc3ded5c33 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 RIP: 0010:virtqueue_add_outbuf+0x4d/0x110 drivers/virtio/virtio_ring.c:2266 Code: 4c 24 10 89 54 24 0c 49 89 f6 48 89 fb 65 48 8b 04 25 28 00 00 00 48 89 44 24 60 49 bc 00 00 00 00 00 fc ff df 4c 8d 6c 24 40 <48> c7 44 24 20 b3 8a b5 41 48 c7 44 24 28 1c 1b f0 8d 48 c7 44 24 RSP: 0018:ffffc900036e6a20 EFLAGS: 00000282 RAX: 95eba803e0b81e00 RBX: ffff8880275df400 RCX: ffff88807c3054f0 RDX: 0000000000000003 RSI: ffff888027b70460 RDI: ffff8880275df400 RBP: ffffc900036e6ad0 R08: 0000000000000820 R09: 1ffffffff1fee70d R10: dffffc0000000000 R11: fffffbfff1fee70e R12: dffffc0000000000 R13: ffffc900036e6a60 R14: ffff888027b70460 R15: 0000000000000003 FS: 00007f557c59b800(0000) GS:ffff8880b8900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7af31ff000 CR3: 000000007a214000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: xmit_skb drivers/net/virtio_net.c:3043 [inline] start_xmit+0xfe4/0x22e0 drivers/net/virtio_net.c:3072 __netdev_start_xmit include/linux/netdevice.h:4916 [inline] netdev_start_xmit include/linux/netdevice.h:4925 [inline] xmit_one net/core/dev.c:3588 [inline] dev_hard_start_xmit+0x27a/0x7e0 net/core/dev.c:3604 sch_direct_xmit+0x29c/0x5d0 net/sched/sch_generic.c:343 __dev_xmit_skb net/core/dev.c:3817 [inline] __dev_queue_xmit+0x1a74/0x3e80 net/core/dev.c:4390 dev_queue_xmit include/linux/netdevice.h:3094 [inline] neigh_hh_output include/net/neighbour.h:526 [inline] neigh_output include/net/neighbour.h:540 [inline] ip_finish_output2+0xd41/0x1390 net/ipv4/ip_output.c:236 ip_local_out net/ipv4/ip_output.c:130 [inline] __ip_queue_xmit+0x118c/0x1b80 net/ipv4/ip_output.c:536 __tcp_transmit_skb+0x2544/0x3b30 net/ipv4/tcp_output.c:1466 tcp_transmit_skb net/ipv4/tcp_output.c:1484 [inline] tcp_write_xmit+0x17b5/0x6bf0 net/ipv4/tcp_output.c:2830 __tcp_push_pending_frames+0x9b/0x360 net/ipv4/tcp_output.c:3015 tcp_sendmsg_locked+0x45f9/0x50a0 net/ipv4/tcp.c:1325 tcp_sendmsg+0x30/0x50 net/ipv4/tcp.c:1357 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x1a6/0x270 net/socket.c:745 sock_write_iter+0x2d7/0x3f0 net/socket.c:1166 new_sync_write fs/read_write.c:590 [inline] vfs_write+0xa6d/0xc90 fs/read_write.c:683 ksys_write+0x1a0/0x2c0 fs/read_write.c:736 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f557c955bf2 Code: 89 c7 48 89 44 24 08 e8 7b 34 fa ff 48 8b 44 24 08 48 83 c4 28 c3 c3 64 8b 04 25 18 00 00 00 85 c0 75 20 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 6f 48 8b 15 07 a2 0d 00 f7 d8 64 89 02 48 83 RSP: 002b:00007ffffa970818 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000074 RCX: 00007f557c955bf2 RDX: 0000000000000074 RSI: 000055fea78d9960 RDI: 0000000000000004 RBP: 000055fea78e7220 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000055fe6bfaeaa4 R13: 00000000000001ae R14: 000055fe6bfaf3e8 R15: 00007ffffa970888 INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 2.155 msecs